NJ2340 bearing: complete specifications & equivalents
The NJ2340 is a ISO 15 radial bearing sized 200 x 420 x 138 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 200 mm |
| Outer diameter D | 420 mm |
| Width B | 138 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 1680 kN |
| Basic static load rating C0 | 2240 kN |
| Fatigue load limit Pu | 195 kN |
| Limiting speed (mechanical) | 1400 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 90700 g |
| Manufacturer designation | NTN NJ2340 |
| Standard | ISO 15 |
| Catalog version | NTN Ball and Roller Bearings CAT.No.2203E |
| Last verified | 2026-10-01 |
Source: catalog reference (NTN Ball and Roller Bearings CAT.No.2203E) · extracted 2026-10-01
Parameters extracted from the official NTN Ball and Roller Bearings catalogue (NTN Ball and Roller Bearings CAT.No.2203E); NTN® is a trademark of NTN Corporation, used here for identification only — mpnbase is not an authorized NTN distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at ntnglobal.com.
Dimensions in inches & NJ2300-series range
| Bore d | 7.874 in |
|---|---|
| Outer diameter D | 16.535 in |
| Width B | 5.433 in |
| ISO bore code | 40 |
| Radial section height (D−d)/2 | 110 mm |
| Smallest bore in NJ2300-series | 20 mm |
| Largest outer diameter in NJ2300-series | 580 mm |
| Width range across NJ2300-series | 21–175 mm |
| Bore position in NJ2300-series (smallest first) | 27 of 31 |
| Bore above smallest NJ2300-series size | 180 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NJ2340-ECML | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 200×420×138 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting. |
Interchange levels: full standard interchange · partial verify parameters · verify manual confirmation required. Links resolve to the equivalent model's specification page where available.
How the NJ2340 model number is decoded
NJ2340 belongs to the NTN cylindrical roller range in NTN Ball and Roller Bearings CAT.No.2203E: line-contact rollers between ground raceways for a 1680 kN dynamic rating in the 200 mm bore. On the NTN nameplate NJ states which ring carries the ribs, which determines whether NJ2340 floats or locates; the numeric remainder is the ISO 15 series and 200 mm bore reference, not a fit or clearance instruction. With C 1680 kN and C0 2240 kN (C0/C ≈ 1.33) the bearing is proportioned for heavy radial load; the NJ design accepts axial load in one direction and provides one-way shaft location. Speed ratio check: limiting 1,400 r/min is .88 of the 1,600 r/min oil value for NJ2340; grease-churn heating closes that gap as fill quantity rises. Keep the open bearing wrapped until fitting: the line-contact raceways of the 200 mm bore indent under a single hard particle, and the steel cage provides no sealing of its own.
Typical equipment & failure modes
Common applications
- rolling-mill work-roll and backup-roll positions
- large turbine and generator rotor bearings
- wind-turbine gearbox planet and rotor shafts
- ship propulsion line shafts and reduction gears
Known failure patterns
- roller smearing (microwelding) at start-up before the oil film builds under insufficient radial load
- cage distortion after a mounting blow carried through the roller set
- grease starvation and cage drag when relubrication intervals are extended past the grease life
- false brinelling on standby machines exposed to external vibration
- hard-particle indentation of raceways in unfiltered oil or open arrangements
Selection pitfalls — read before you substitute
- At 200 mm bore, oil-lubricated arrangements toward 1,600 r/min need positive flow and drain design; the 90700 g NJ2340 ring stores enough heat that grease-only duty needs a careful relubrication calculation.
- Open NJ2340 units need application-supplied sealing and a defined lubricant schedule; film thickness is the first failure mode for line contact when viscosity drops at the 200 mm contact.
- Never press either ring through the roller complement when fitting: mounting force goes through the ring faces, or the 420 mm race brinells and releases as vibration within hours.
- Wide (22/23) and light (10/49) executions at 200 mm bore share bore but not OD/width; check the full NJ2300 series code before substituting, because housing and shoulder geometry will not interchange.
- Minimum radial load is frequently missed in oversized motor and fan selections: an underloaded NJ2340 skids at 1,400 r/min and fails by smearing long before L10 fatigue.
- The 1680/2240 kN ratings, 195 kN Pu and 90700 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NJ2340 (standard execution); other makes sharing the ISO 15 envelope revise internal geometry without changing the order number, so keep the 2203E reference with the specification for critical drives.
Frequently asked questions
What are the dimensions and catalogue data of NJ2340?
NJ2340 is an NTN NJ single-row cylindrical roller bearing to ISO 15: 200 mm bore, 420 mm OD and 138 mm width (7.874 × 16.535 × 5.433 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1680 kN, C0 2240 kN, Pu 195 kN, grease limiting speed 1,400 r/min, oil 1,600 r/min, mass about 90700 g. It is open, with a pressed sheet-steel cage.
What is the difference between NU, NJ, NUP, N and NF cylindrical roller bearings?
The prefix states the rib arrangement: NU has two outer-ring ribs and a ribless inner ring (float, no axial load); NJ adds ribs for one-direction location; NUP adds a loose L-ring to locate both directions; N has two inner-ring ribs and a separable outer ring; NF has one rib per ring for one-direction guidance. NJ2340 is two integral ribs on the inner ring and one rib on the outer ring — it locates the shaft in one axial direction.
What do the EA, E and ＊ suffixes mean on NTN cylindrical roller bearings?
EA is NTN's high-capacity design with a pressed sheet-steel cage and optimised roller complement in the same ISO 15 envelope; E marks the high-capacity design at the larger bores; the ＊ symbol printed before the code in the NTN catalogue marks the ULTAGE new-generation specification and is not typed as part of the order number. NJ2340 is supplied in the standard open execution shown in the table.
Can NJ2340 take axial load and locate a shaft?
the NJ design accepts axial load in one direction and provides one-way shaft location. For two-direction location use an NUP execution or an NJ pair with loose rib rings.
What do Fw and Ew mean for NJ2340?
Fw is the inner sub-assembly raceway/roller-set envelope diameter and Ew the outer-ring raceway diameter printed for geometric checks: Fw 260 mm, Ew 360 mm. The nominal bore/OD remain 200/420 mm; Fw/Ew describe the rolling-contact path, and speeds still run to 1,400 r/min grease / 1,600 r/min oil.
Reviewed & verified by the MPN Base engineering desk against source catalog NTN Ball and Roller Bearings CAT.No.2203E on 2026-10-01. Read our editorial & correction policy.